Edge-locking and quantum control in highly polarized spin chains

TL;DR

This paper introduces edge-locking states in anisotropic Heisenberg spin chains, enabling precise quantum control by manipulating edge-polarized blocks, with potential applications in quantum information transfer.

Contribution

It reveals the existence of edge-locked states in XXZ spin chains and demonstrates how they can be controlled through minimal spin flips, advancing quantum state manipulation techniques.

Findings

Edge-locking states exist in anisotropic Heisenberg chains.

Edge-locking can be controlled by flipping a few spins.

Hierarchy of edge-locking effects depends on anisotropy.

Abstract

For an open-boundary spin chain with anisotropic Heisenberg (XXZ) interactions, we present states in which a connected block near the edge is polarized oppositely to the rest of the chain. We show that such blocks can be `locked' to the edge of the spin chain, and that there is a hierarchy of edge-locking effects at various orders of the anisotropy. The phenomenon enables dramatic control of quantum state transmission: the locked block can be freed by flipping a single spin or a few spins.